Buggy code:
public class HashCodeBuilder { private static final ThreadLocal < Set < IDKey > > registry = new ThreadLocal < Set < IDKey > > ( ) { @ Override protected Set < IDKey > initialValue ( ) { } } ; static Set < IDKey > getRegistry ( ) { } static boolean isRegistered ( Object value ) { } private static void reflectionAppend ( Object object , Class < ? > clazz , HashCodeBuilder builder , boolean useTransients , String [ ] excludeFields ) { if ( HashCodeBuilder . isRegistered ( object ) ) { return ; } try { HashCodeBuilder . register ( object ) ; Field [ ] fields = clazz . getDeclaredFields ( ) ; <START_BUG> List < String > excludedFieldList = ( excludeFields != null ) ? Arrays . asList ( excludeFields ) : Collections . EMPTY_LIST ; <END_BUG> AccessibleObject . setAccessible ( fields , true ) ; for ( Field field : fields ) { if ( ( ( ( ! ( excludedFieldList . contains ( field . getName ( ) ) ) ) && ( ( field . getName ( ) . indexOf ( '$' ) ) == ( - 1 ) ) ) && ( useTransients || ( ! ( Modifier . isTransient ( field . getModifiers ( ) ) ) ) ) ) && ( ! ( Modifier . isStatic ( field . getModifiers ( ) ) ) ) ) { try { Object fieldValue = field . get ( object ) ; builder . append ( fieldValue ) ; } catch ( IllegalAccessException e ) { throw new InternalError ( "Unexpected<seq2seq4repair_space>IllegalAccessException" ) ; } } } } finally { HashCodeBuilder . unregister ( object ) ; } } public static int reflectionHashCode ( int initialNonZeroOddNumber , int multiplierNonZeroOddNumber , Object object ) { } public static int reflectionHashCode ( int initialNonZeroOddNumber , int multiplierNonZeroOddNumber , Object object , boolean testTransients ) { } public static < T > int reflectionHashCode ( int initialNonZeroOddNumber , int multiplierNonZeroOddNumber , T object , boolean testTransients , Class < ? super T > reflectUpToClass ) { } public static < T > int reflectionHashCode ( int initialNonZeroOddNumber , int multiplierNonZeroOddNumber , T object , boolean testTransients , Class < ? super T > reflectUpToClass , String [ ] excludeFields ) { } public static int reflectionHashCode ( Object object ) { } public static int reflectionHashCode ( Object object , boolean testTransients ) { } public static int reflectionHashCode ( Object object , Collection < String > excludeFields ) { } public static int reflectionHashCode ( Object object , String [ ] excludeFields ) { } static void register ( Object value ) { } static void unregister ( Object value ) { } private final int iConstant ; private int iTotal = 0 ; public HashCodeBuilder ( ) { } public HashCodeBuilder ( int initialNonZeroOddNumber , int multiplierNonZeroOddNumber ) { } public HashCodeBuilder append ( boolean value ) { } public HashCodeBuilder append ( boolean [ ] array ) { } public HashCodeBuilder append ( byte value ) { } public HashCodeBuilder append ( byte [ ] array ) { } public HashCodeBuilder append ( char value ) { } public HashCodeBuilder append ( char [ ] array ) { } public HashCodeBuilder append ( double value ) { } public HashCodeBuilder append ( double [ ] array ) { } public HashCodeBuilder append ( float value ) { } public HashCodeBuilder append ( float [ ] array ) { } public HashCodeBuilder append ( int value ) { } public HashCodeBuilder append ( int [ ] array ) { } public HashCodeBuilder append ( long value ) { } public HashCodeBuilder append ( long [ ] array ) { } public HashCodeBuilder append ( Object object ) { } public HashCodeBuilder append ( Object [ ] array ) { } public HashCodeBuilder append ( short value ) { } public HashCodeBuilder append ( short [ ] array ) { } public HashCodeBuilder appendSuper ( int superHashCode ) { } public int toHashCode ( ) { } public int hashCode ( ) { } }

Fix:
List < String > excludedFieldList = ( excludeFields != null ) ? Arrays . asList ( excludeFields ) : Collections . < String > emptyList ( ) ;